Best JavaScript code snippet using jest
pkgs.js
Source: pkgs.js
1var pkgs = {2 stdenv : function() {3 return require('./pkgs/stdenv.js').pkg;4 },5 fetchurl : function() {6 return require('./pkgs/fetchurl').pkg({7 stdenv : pkgs.stdenv8 });9 },10 hello : function() {11 return require('./pkgs/hello.js').pkg({12 stdenv : pkgs.stdenv,13 fetchurl : pkgs.fetchurl14 });15 },16 zlib : function() {17 return require('./pkgs/zlib.js').pkg({18 stdenv : pkgs.stdenv,19 fetchurl : pkgs.fetchurl20 });21 },22 file : function() {23 return require('./pkgs/file.js').pkg({24 stdenv : pkgs.stdenv,25 fetchurl : pkgs.fetchurl,26 zlib : pkgs.zlib27 });28 },29 perl : function() {30 return require('./pkgs/perl.js').pkg;31 },32 openssl : function() {33 return require('./pkgs/openssl.js').pkg({34 stdenv : pkgs.stdenv,35 fetchurl : pkgs.fetchurl,36 perl : pkgs.perl,37 zlib : pkgs.zlib38 });39 },40 curl : function() {41 return require('./pkgs/curl.js').pkg({42 stdenv : pkgs.stdenv,43 fetchurl : pkgs.fetchurl,44 openssl : pkgs.openssl,45 zlib : pkgs.zlib46 });47 },48 wget : function() {49 return require('./pkgs/wget.js').pkg({50 stdenv : pkgs.stdenv,51 fetchurl : pkgs.fetchurl,52 openssl : pkgs.openssl53 });54 },55 sumTest : function() {56 return require('./pkgs/sumTest.js').pkg({57 stdenv : pkgs.stdenv58 })59 },60 writeTextFile : function(args) {61 return require('./pkgs/writeTextFile.js').pkg(args);62 },63 stringWriteTest : function () {64 return require('./pkgs/stringWriteTest.js').pkg({65 writeTextFile : pkgs.writeTextFile66 });67 },68 appendFilesTest : function() {69 return require('./pkgs/appendFilesTest.js').pkg({70 stdenv : pkgs.stdenv71 });72 },73 createFileWithMessageTest : function() {74 return require('./pkgs/createFileWithMessageTest.js').pkg({75 stdenv : pkgs.stdenv76 });77 },78 sayHello : function() {79 return require('./pkgs/sayHello.js').pkg({80 stdenv : pkgs.stdenv81 });82 },83 addressPerson : function() {84 return require('./pkgs/addressPerson.js').pkg({85 stdenv : pkgs.stdenv86 });87 },88 addressPersons : function() {89 return require('./pkgs/addressPersons.js').pkg({90 stdenv : pkgs.stdenv91 });92 },93 addressPersonInformally : function() {94 return require('./pkgs/addressPersonInformally.js').pkg({95 stdenv : pkgs.stdenv96 });97 },98 numbers : function() {99 return require('./pkgs/numbers.js').pkg({100 stdenv : pkgs.stdenv101 });102 },103 sayHello2 : function() {104 return require('./pkgs/sayHello2.js').pkg({105 stdenv : pkgs.stdenv106 });107 },108 objToXML : function() {109 return require('./pkgs/objToXML.js').pkg({110 writeTextFile : pkgs.writeTextFile111 });112 },113 conditionals: function() {114 return require('./pkgs/conditionals.js').pkg({115 writeTextFile : pkgs.writeTextFile116 });117 },118 bzip2 : function() {119 return require('./pkgs/bzip2.js').pkg({120 stdenv : pkgs.stdenv,121 fetchurl : pkgs.fetchurl122 });123 },124 utillinux : function() {125 return require('./pkgs/utillinux.js').pkg({126 stdenv : pkgs.stdenv,127 fetchurl : pkgs.fetchurl,128 zlib : pkgs.zlib129 });130 },131 python : function() {132 return require('./pkgs/python').pkg({133 stdenv : pkgs.stdenv,134 fetchurl : pkgs.fetchurl,135 zlib : pkgs.zlib,136 bzip2 : pkgs.bzip2,137 openssl : pkgs.openssl,138 });139 },140 nodejs : function() {141 return require('./pkgs/nodejs').pkg({142 stdenv : pkgs.stdenv,143 fetchurl : pkgs.fetchurl,144 python : pkgs.python,145 zlib : pkgs.zlib,146 openssl : pkgs.openssl,147 utillinux : pkgs.utillinux148 });149 },150 buildNodePackage : function() {151 return require('./pkgs/nodejs/buildNodePackage.js').pkg({152 stdenv : pkgs.stdenv,153 nodejs : pkgs.nodejs154 });155 },156 optparse : function() {157 return require('./pkgs/optparse.js').pkg({158 buildNodePackage : pkgs.buildNodePackage,159 fetchurl : pkgs.fetchurl160 });161 },162 slasp : function() {163 return require('./pkgs/slasp.js').pkg({164 buildNodePackage : pkgs.buildNodePackage,165 fetchurl : pkgs.fetchurl166 });167 },168 nijs : function() {169 return require('./pkgs/nijs.js').pkg({170 buildNodePackage : pkgs.buildNodePackage,171 fetchurl : pkgs.fetchurl,172 optparse : pkgs.optparse,173 slasp : pkgs.slasp174 });175 },176 underscoreTest : function() {177 return require('./pkgs/underscoreTest.js').pkg;178 },179 HelloModel : function() {180 return require('./pkgs/HelloModel.js').pkg({181 stdenv : pkgs.stdenv,182 fetchurl : pkgs.fetchurl183 });184 }185};...
build.js
Source: build.js
...41 stdout.write(42 `${watch ? 'Build-watching' : 'Building'} ${bold(pkgName)}...\n`43 );44 if (nodePackages.indexOf(pkgName) !== -1) {45 await buildNodePackage(pkgName);46 } else {47 await buildBrowserPackage(pkgName);48 }49 } else {50 if (watch) {51 // The limitation here is that we need to build browser packages after52 // packages compiled with Babel. This doesn't work out of the box because53 // `buildNodePackage` hangs forever in watch mode.54 stderr.write(55 error(56 `Can't build-watch all packages! Run ${italic(57 'build PACKAGE --watch'58 )} for one or more packages (in separate terminals)\n`59 )60 );61 return;62 }63 stdout.write(`Building packages...\n`);64 await Promise.all(nodePackages.map(buildNodePackage));65 stdout.write(`Building browser packages...\n`);66 await Promise.all(browserPackages.map(buildBrowserPackage));67 stdout.write(`Built ${buildablePackages.length} packages successfully.\n`);68 }69}70function getFormattedPackageList(pkgNames) {71 return ['', ...pkgNames].join('\n - ');72}73async function buildNodePackage(pkgName) {74 return runBuildTask({75 pkgName,76 cmd: 'babel',77 args: getBabelCliArgs(pkgName)78 });79}80async function buildBrowserPackage(pkgName) {81 return runBuildTask({82 pkgName,83 cmd: 'webpack',84 args: getWebpackCliArgs(pkgName),85 env: { NODE_ENV: 'production' }86 });87}...
babelNodePackage.js
Source: babelNodePackage.js
...25 // console.log('not found: ../../../.bin/babel')26 }27 return spawn(path, args)28}29function buildNodePackage(30 name,31 root,32 src,33 pathBuild,34 watch = false,35 babelArgs = ['--env-name', 'node', '--copy-files', '--extensions', '.ts', '--extensions', '.js', '--ignore', '**/*.d.ts'],36) {37 return new Promise((resolve, reject) => {38 const dist = path.resolve(root, pathBuild)39 let args = [root + '/' + src, ...babelArgs]40 if(watch) {41 args.push('-w')42 }43 args.push(...['--out-dir', dist])...
build-node-packages.js
Source: build-node-packages.js
1/*2 Copyright 2018 Google LLC3 Use of this source code is governed by an MIT-style4 license that can be found in the LICENSE file or at5 https://opensource.org/licenses/MIT.6*/7const gulp = require('gulp');8const buildNodePackage = require('./utils/build-node-package');9const packageRunnner = require('./utils/package-runner');10gulp.task('build-node-packages', gulp.series(11 packageRunnner(12 'build-node-packages',13 'node',14 buildNodePackage,15 ),...
slasp.js
Source: slasp.js
1var nijs = require('nijs');2exports.pkg = function(args) {3 return args.buildNodePackage()({4 name : "slasp-0.0.4",5 src : args.fetchurl()({6 url : new nijs.NixURL("http://registry.npmjs.org/slasp/-/slasp-0.0.4.tgz"),7 sha1 : "9adc26ee729a0f95095851a5489f87a5258d57a9"8 }),9 10 meta : {11 description : "SugarLess Asynchronous Structured Programming"12 }13 });...
nijs.js
Source: nijs.js
1var nijs = require('nijs');2exports.pkg = function(args) {3 return args.buildNodePackage()({4 name : "nijs-0.0.25",5 src : new nijs.NixFile({6 value : "../..",7 module : module8 }),9 deps : [10 args.optparse(),11 args.slasp()12 ],13 14 meta : {15 description : "An internal DSL for Nix in JavaScript"16 }17 });...
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Since Jest tests are runtime tests, they only have access to runtime information. You're trying to use a type, which is compile-time information. TypeScript should already be doing the type aspect of this for you. (More on that in a moment.)
The fact the tests only have access to runtime information has a couple of ramifications:
If it's valid for getAll
to return an empty array (because there aren't any entities to get), the test cannot tell you whether the array would have had Entity
elements in it if it hadn't been empty. All it can tell you is it got an array.
In the non-empty case, you have to check every element of the array to see if it's an Entity
. You've said Entity
is a class, not just a type, so that's possible. I'm not a user of Jest (I should be), but it doesn't seem to have a test specifically for this; it does have toBeTruthy
, though, and we can use every
to tell us if every element is an Entity
:
it('should return an array of Entity class', async () => {
const all = await service.getAll()
expect(all.every(e => e instanceof Entity)).toBeTruthy();
});
Beware, though, that all calls to every
on an empty array return true
, so again, that empty array issue raises its head.
If your Jest tests are written in TypeScript, you can improve on that by ensuring TypeScript tests the compile-time type of getAll
's return value:
it('should return an array of Entity class', async () => {
const all: Entity[] = await service.getAll()
// ^^^^^^^^^^
expect(all.every(e => e instanceof Entity)).toBeTruthy();
});
TypeScript will complain about that assignment at compile time if it's not valid, and Jest will complain at runtime if it sees an array containing a non-Entity
object.
But jonrsharpe has a good point: This test may not be useful vs. testing for specific values that should be there.
Check out the latest blogs from LambdaTest on this topic:
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|<p>it('check_object_of_Car', () => {</p><p>
expect(newCar()).toBeInstanceOf(Car);</p><p>
});</p>|
| :- |
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